LIBRARY 

OP  THK 

UNIVERSITY  OF  CALIFORNIA. 

Class 


MOLDING  CONCRETE  BATH  TUBS, 
AQUARIUMS    AND    NATATORIUMS 


Houghton's  Concrete  Worker's 
Reference  Books 

POPULAR    50c.    HAND    BOOKS 


Concrete  Wall  Forms  .  .  .  .  50c. 
Concrete  Floors  and  Sidewalks  .  .  SOc. 
Practical  Silo  Construction  .  .  50c. 

Molding  Concrete  Chimneys,  Slate  and 

Roof  Tiles SOc. 

Molding  and  Curing  Ornamental  Concrete  SOc. 
Concrete  Monuments,  Mausoleums  and 

Burial  Vaults SOc. 

Molding  Concrete  Bath  Tubs,  Aquariums 

and  Natatoriums  ....  SOc. 
Artistic  Concrete  Bridges  .  .  .SOc. 
Constructing  Concrete  Porches  .  .SOc. 
Molding  Concrete  Flower  Pots,  Boxes, 

Jardinieres,  Etc.  .  .  .  .SOc. 
Molding  Concrete  Fountains  and  Lawn 

Ornaments SOc. 

Concrete  for  the  Farm  and  Shop  .  .SOc. 

Houghton's  Other  Practical  Concrete  Books 

Concrete  from  Sand  Molds  .  .  .  12.00 
Ornamental  Concrete  Without  Molds  .  2.00 

A  *  pedal  circular  of  an*  of  the  book*  tail!  be  tent  on  rtquett. 
Any  of  these  bock*  tent  prepaid  on  receipt  of  the  price. 


THE  NORMAN  W.  HENLEY  PUBLISHING  Co. 

132   NASSAU  STREET.  NEW  YORK 


MOLDING  CONCRETE 
BATH  TUBS,  AQUARIUMS 
AND  NATATORIUMS 


A     PRACTICAL     TREATISE 

EXPLAINING  THE  MOLDING  IN  CONCRETE  OF  VARIOUS 
STYLES  OF  BATH  TUBS,  LAUNDRY  TRAYS,  ETC.,  WITH 
EASILY  CONSTRUCTED  MOLDS  FOR  THE  PURPOSE.  THE 
MOLDING  OF  AQUARIUMS  AND  NATATORIUMS,  AS  WELL 
AS  THE  WATER-PROOFING  METHODS  USED  FOR  SAME, 
ARE  FULLY  TREATED. 


By 
A.    A.    HOUGHTON 

Author  of  "  Concrete  from  Sand  Molds,"  "  Ornamental  Concrete 
Without  Molds,"  Etc.,  Etc 


Fully  Illustrated  by  Original  Drawings. 


NEW  YORK 

THE    NORMAN    W.    HENLEY   PUBLISHING   CO. 

132  NASSAU  STREET 

1911 


<!:*<• 


COPYRIGHTED,  1911, 

BY 
THE  NOEMAN  W.  HENLEY  PUBLISHING  Co. 


HOAGLAND-ADAMS    CO. 

Printers — Binders — Electrotypers 

476  West  Broadway,   New  York,  U.S.A. 


J 


FOREWORD 

IT  is  the  purpose  of  the  writer  to  present  in  this 
series  of  books  a  complete  explanation  of  various 
successful  methods  of  concrete  construction  that  may 
be  employed  by  the  beginner  as  well  as  by  the  more 
experienced  worker.  I  shall  endeavor  to  give  the 
details  of  molds  and  ideas  that  are  not  covered  by 
patents,  such  as  may  be  easily  and  cheaply  con- 
structed; hence  the  reader  is  not  compelled  to  pur- 
chase expensive  patented  molds  before  putting  into 
practise  the  many  successful  types  of  concrete  con- 
struction I  have  exhaustively  described  in  this  series. 
There  is  no  practical  value  to  the  reader  in  explain- 
ing a  patented  system  of  construction,  other  than  a 
few  words  on  its  merits,  as  the  owners  of  same  are 
always  pleased  to  give  this  information;  hence  in 
going  outside  the  beaten  track  of  concrete  authors 
and  presenting  ideas,  systems,  and  molds  that  are 
practical,  successful  in  operation,  and,  above  all, 
easily  and  simply  constructed,  I  trust  that  I  have 
merited  the  sincere  gratitude  of  all  fellow  workers 
in  the  concrete  field  who  seek  such  information. 
Yours  very  truly, 

A.  A.  HOUGHTON. 


221002 


PREFACE 

The  writer  has  endeavored  to  treat  the  subject 
of  molding  concrete  bath  tubs  in  a  complete  man- 
ner, employing  only  such  molds  as  are  certain  of 
success,  as  well  as  having  the  advantage  of  being 
easily  and  simply  constructed. 

The  close  imitation  of  the  usual  type  of  marble, 
metal  or  composition  tub  is  not  essential,  even  if 
it  is  desirable,  as  concrete  is  an  entirely  different 
material,  demanding  more  massive  lines  to  be 
durable ;  hence,  other  than  upon  the  point  of  use, 
the  concrete  bath  tub  should  be  molded  and  sold 
as  concrete,  and  upon  its  merits  as  concrete,  and 
not  as  an  imitation  of  any  other  material. 

This,  of  course,  should  not  be  construed  to  mean 
that  the  molding  of  smooth,  glossy  concrete  that 
will  reflect  light,  like  polished  stone,  in  any  man- 
ner detracts  from  the  beauty  of  the  material,  nor 
can  this  be  judged  to  be  an  imitation  of  stone,  as 
this  is  but  an  artificial  finish  to  any  product,  and 
is  as  permissible  for  concrete  as  for  any  other 
material. 

The  simple  construction  of  the  molds  for  this 
work,  as  are  fully  illustrated  in  this  volume,  will 
convince  the  reader  that  the  molding  of  concrete 


PREFACE 

bath  tubs  is  extremely  practical,  and  that  there 
should  be  a  most  excellent  sale  for  the  finished 
product  in  competition  with  the  marble  and  met.il 
tubs  for  this  purpose,  as  a  concrete  bath  tub  may 
be  molded  and  sold  at  a  price  far  less  than  of 
other  material,  and  yet  yield  the  worker  a  good 
profit  for  his  work. 

Concrete  may  also  be  made  an  ideal  materi.il 
for  aquariums,  as  it  is  for  natatoriums.  The  sim- 
ple and  easy  method  of  molding  the  work  with 
glass  inserted  into  the  sides,  will  be  of  interest  to 
those  who  have  contemplated  any  work  of  this 
kind. 

Concrete  laundry  trays  or  tubs  are  extremely 
practical,  and  at  the  low  cost  of  same,  with  the 
simplicity  and  ease  of  molding,  should  make  them 
a  profitable  side  line  for  every  concrete  plant. 

The  subject  of  water-proofing  concrete  is  one  of 
great  interest,  while  the  writer  does  not  believe 
that  the  most  positive  and  successful  method  for 
all  classes  of  work  has  yet  been  discovered,  yet  a 
description  of  the  best  known  methods  and  mate- 
rials in  use  to-day  may  be  of  use  and  value  to  the 
reader  who  wants  to  make  the  best  choice  for  the 
type  of  work  under  construction. 

A.  A.  HOUGHTON. 

April,  1911. 


TABLE  OF  CONTENTS 

PAGE 

PROPORTIONING  AND  MIXING  THE  CONCRETE    .  .        .        .13 

CONSTRUCTION  OF  THE  CORE   .        ,        .        .  .4        .14 

MOLDS  FOR  BATH  TUBS  . "      .        .        .       .  •  .       .        .    16 

MOLDING  RIM  OF  BATH  TUBS  .        .                .  .        .        .21 

THE  PLASTER  SYSTEM  OF  MOLDING  BATH  TUBS  .                .25 

MOLDING  THE  SQUARE  STYLE  OF  BATH  TUB  .  .        .        .27 

MOLDING  THE  LEGS  UPON  BATH  TUBS    .        .  .        .        .28 

MOLDING  CONCRETE  LAVATORIES,  SINKS  AND  CLOSET  BOWLS  .    30 

MOLDING  CONCRETE  LAUNDRY   TUBS       .        .  .        ...    36 

MOLDING  A  CONCRETE  AQUARIUM    .        .       .  •       .        .    41 

DESIGN  FOR  A  LARGE  CONCRETE  AQUARIUM     '•  *        .        .45 

CONCRETE  AQUARIUMS  FOR  OUTSIDE  USE        .  .        •        .47 

MOLDING  A  CONCRETE  NATATORIUM  .        •        .    49 

WATER-PROOFING  CONCRETE       .        .        •  .-    •  .        •        .53 

VARIOUS  METHODS  OF  WATER-PROOFING   .        .  .        .        .54 

USE  OF  PATENT  COMPOUNDS  FOR  WATER-PROOFING  CONCRETE  .    59 


Molding   Concrete   Bath   Tubs,  Aqua- 
riums and  Natatoriums 

The  concrete  bath  tub,  as  well  as  any  article 
molded  in  concrete  and  intended  to  retain  water, 
should  be  of  such  a  mixture  as  to  secure  the  maxi- 
mum density  of  the  concrete.  This  is  an  aid  in 
making  the  work  water-proof,  as  the  closing  of  the 
pores  is  accomplished,  thus  demanding  less  treat- 
ment to  make  a  thoroughly  water-proof  product. 

To  secure  the  maximum  density,  without  pres- 
sure, the  concrete  must  be  of  a  wet  mix,  so  that 
it  can  be  poured  and  thus  flow  to  every  part  of  the 
mold.  This  permits  the  molds  to  have  a  smaller 
opening  for  placing  the  concrete  than  if  the  mix- 
ture was  to  be  tamped  into  the  molds. 

The  addition  of  from  one-tenth  and  one-fourth 
to  equal  parts  of  hydrated  lime,  in  proportion  to 
the  cement  used,  is  also  of  value,  as  the  extreme 
fineness  of  the  lime  causes  it  to  fill  the  voids  or 
pores  in  the  concrete,  thus  increasing  the  density 
of  the  work.  With  a  rich  mixture  of  concrete  and 
the  addition  of  lime,  usually  about  25%  of  the 
weight  of  the  cement,  work  may  be  molded  by 
the  wet  process  that  is  practically  water-proof; 
at  the  worst  demanding  but  the  minimum  of  spe- 

13 


14  MOLDING   CONCRETE   BATH   TUBS, 

cial  treatment  to  render  it  absolutely  water-tight. 

The  sand  for  this  work,  when  used  for  a  bath 
tub  or  small  aquarium,  should  run  from  coarse  to 
fine  particles,  and  be  clean  and  sharp  without  the 
presence  of  any  loam  or  clay;  this  may  be  tested 
by  placing  in  water  and  allowing  to  settle,  when 
the  presence  of  any  dirt  may  be  easily  detected. 
The  necessity  for  clean  and  well-graded  aggregate 
is  greater  where  the  work  does  not  have  the  body 
or  wall  thickness  to  give  it  the  needful  strength. 

The  rdost  successful  mixture  for  a  bath  tub  or 
small  aquarium  is  secured  when  in  the  proportion 
of  1:3,  using  sand  as  the  aggregate;  to  this  may 
be  added  25%  of  hydrated  lime  with  beneficial  re- 
sults, based  on  the  weight  of  the  cement  used. 
Thus,  for  each  sack  of  cement,  25  pounds  of  lime 
are  added  to  the  mixture.  The  concrete  should 
be  wet  enough  to  be  poured  from  a  pail  into  the 
molds  or  forms,  pouring  it  slowly  so  to  permit  th<* 
grout  to  flow  to  all  parts  of  the  mold.  This  will 
insure  the  maximum  density,  as  well  as  the 
strongest  bond  between  the  concrete  and  rein- 
forcement, which  should  be  added  where  the  walls 
are  less  than  2  inches  in  thickness  at  any  point. 

CONSTRUCTION   OF  THE   CORE 

At  Fig.  1,  is  shown  one  of  the  simplest  forms  of 
constructing  a  core  for  a  concrete  bath  tub  mold. 
This  is  built  of  sheet  steel,  bent  over  a  wood  form, 
to  give  it  the  shape  or  outline  desired.  This 


AQUAEIUMS    AND    NATATOEIUMS. 


15 


FIG.    1. — Construction    of    core    for   concrete    bath   tub. 


16  MOLDING   CONCRETE    BATH   TUBS, 

should  be  less  in  width  at  the  bottom  than  at  the 
top,  so  to  give  a  tapering  or  wedge-shaped  form, 
which  is  the  more  easily  drawn  from  the  com- 
pleted work. 

The  ends  are  cut  in  a  convex  form,  as  illus- 
trated, and  then  securely  fastened  to  two  straight 
strips  that  make  the  sides  of  the  core,  at  top  and 
bottom  of  same.  The  sheet  metal  for  the  sides 
of  the  core  should  be  No.  27  or  28  gauge,  so  to 
be  the  more  easily  bent  to  fit  the  wood  form ;  that 
for  the  sides  is  cut  the  exact  width  and  nailed  to 
the  wood  strips  at  top  and  bottom.  The  bottom 
of  mold  is  covered  by  a  sheet  of  the  metal,  cut  to 
fit  the  core  form  at  bottom. 

The  core  mold  should  be  well  coated  with  oil 
before  use,  or  by  giving  two  coats  of  enamel,  tlx» 
surface  will  be  less  liable  to  stick  to  the  concrete, 
permitting  the  core  to  be  withdrawn  with  ease 
and  success. 

While  the  core  in  illustrations  is  shown  with 
oval  ends,  as  that  is  the  most  satisfactory  form, 
yet  the  worker  may  easily  adapt  the  method  of 
construction,  to  a  square  form  as  well  as  to  any 
other  type  he  may  prefer. 

MOLDS  FOR  BATH  TUBS 

As  shown  in  the  illustration  at  Fig.  2,  the  bath 
tub  is  molded  bottom  upward,  which  brings  the 
trowel  finish  upon  the  bottom  of  the  tub,  and  also 
permits  the  legs  to  be  the  more  successfully 


AQUAEIUMS    AND    NATATORIUMS. 


17 


FIG.  2. — Mold  for  bath  tub  of  concrete. 


18 


MOLDING   CONCRETE    BATH   TUBS, 


molded.  The  core  form  is  inverted  in  the  center 
of  the  molding  board,  or  mold  for  the  rim  of  tub, 
and  is  held  in  position  by  blocks  or  cleats  nailed 
to  the  molding  board.  The  forms  or  molds  for  the 
outside  of  tub  are  then  placed  around  the  core  ;\\ 
an  equal  distance  from  same  upon  all  sides,  and 
when  the  reinforcement  is  in  position  it  is  then 
ready  for  the  concrete  to  be  poured. 

The  construction  of  the  outside  molds  are 
clearly  shown  in  Fig.  2;  the  two  ends  are  formed 
by  using  concave  strips  of  wood,  cut  to  the  size 
desired  for  the  top  and  bottom  of  tub,  and  with 
the  curve  you  desire  for  the  outside  at  each  end 
of  tub.  The  sides  of  the  mold  are  made  from 
straight  strips  of  the  right  length,  and  these  are 
held  against  the  end  strips,  when  molding  work, 
by  strips  of  strap  iron,  fastened  with  screws  and 
connecting  the  two  pieces  together.  Thus  the 
completed  mold  for  outside  of  tub  is  composed  of 
four  sections,  one  for  each  end  and  two  side  sec- 
tions; these  are  easily  assembled  by  attaching 
the  strap  irons  at  each  joint,  and  as  easily  re- 
moved from  the  completed  work. 

The  inside  of  the  wood  strips  is  lined  with  sheet 
metal,  using  No.  27  or  28  gauge.  This  must  be 
wide  enough  so  that  the  outside  mold  will  be  at 
least  11/2  inches  above  the  core,  when  in  position 
for  molding,  so  as  to  mold  the  bottom  of  the  tub. 
The  inside  or  molding  surface  is  coated  with  any 
good  enamel,  so  to  make  a  smooth  molding  sur- 


AQUARIUMS    AND    NATATOEIUMS.  19 

face  as  well  as  to  prevent  the  mold  from  sticking 
to  the  work. 

The  best  thickness  for  the  walls  of  a  tub  of  this 
style  is  114-inch  for  the  sides,  and  1%  or  2  inches 
for  the  bottom,  reinforced  with  wire  cloth  of 
%-inch  mesh  or  expanded  metal.  The  reinforce- 
ment is  cut  and  bent  into  the  form  of  tub  and  se- 
curely wired  together,  so  that  it  may  be  simply 
set  over  the  core  form  and  will  then  be  exactly  in 
the  center  of  the  molded  wall.  The  reinforce- 
ment may  be  modeled  over  the  core  form  by  lay- 
ing or  lightly  nailing  lath  to  the  outside  of  the 
core,  thus  insuring  that  the  complete  reinforce- 
ment will  be  placed  in  the  center  of  the  wall.  A 
special  wood  form  may  also  be  employed  to  build 
the  reinforcing  metal  into  the  proper  form,  when 
time  is  of  importance.  The  advantage  in  having 
a  wall  of  1%  to  1%  inches  is  that  the  weight  of 
the  completed  tub  is  greatly  reduced,  thus  making 
this  style  of  tub  practical  for  the  purpose.  The 
ample  reinforcement  will  make  a  wall  thickness 
of  1%  inches,  with  a  bottom  thickness  of  1% 
inches,  strong  enough  for  the  work,  and  yet  have 
the  tub  light  enough  to  be  easily  moved  when  it  is 
so  desired. 

The  type  of  metal  lined  mold,  illustrated  in  Fig. 
2,  is  of  the  most  durable  construction,  as  thef  e  is 
no  wood  in  contact  with  the  concrete  whatever.  It 
also  permits  the  outside  metal  to  be  cut  from 
sheet  steel  ceiling  plates,  which  are  stamped  with 


20  MOLDING   CONCRETE   BATH   TUBS, 


FIG.  3. — Plaster  mold  for  rim  of  bath  tub. 


AQUARIUMS    AND    NATATORIUMS.  21 

various  ornamental  forms,  thus  molding  the  out- 
side surface  of  tub  with  bas-relief  ornamentation 
upon  same.  This  feature,  when  properly  done, 
should  make  the  concrete  tub  a  strong  competitor 
of  the  usual  style  among  the  great  mass  of  people 
to  whom  price  as  well  as  appearance  is  of  con- 
sideration. 

MOLDS  FOR  RIM  OF  BATH  TUB 

At  Fig.  3  is  shown  the  method  of  making  a  con- 
crete or  plaster  mold  for  the  rim  of  the  bath  tub. 
The  core  form  is  set  in  the  center  of  the  molding 
board,  inverted,  and  a  square  form  of  wood  strips 
erected  around  same.  These  are  3  inches  in 
height,  and  at  least  6  inches  larger  than  the  core 
form  upon  all  sides.  The  plaster  or  concrete  is 
then  tamped  into  this  form,  and  with  a  trowel  or 
gutter  tool,  the  mortar  is  molded  into  a  concave 
form  of  the  exact  shape  desired  for  the  rim  of 
tub. 

This  may  be  cut  in  sections  or  remain  in  one  en- 
tire section,  as  the  worker  may  desire  for  con- 
venience in  storing.  The  work  is  easily  removed 
from  the  mold  in  either  case.  The  inside  of  the 
plaster  or  concrete  mold  for  rim  should  be  treated 
to  two  coats  of  shellac,  so  to  give  a  smooth  mold- 
ing surface.  When  the  completed  mold  is  assem- 
bled, the  outside  form  will  rest  upon  this  plaster 
mold  for  rim;  this  is  usually  filled  with  the  con- 
crete mixture  for  bath  tub  before  the  outside  mold 


22 


MOLDING   CONCRETE    BATH   TUBS, 


"Fio.  4. — Constructing  a  wood  mold  for  rim  of  bath  tub. 


AQUAKIUMS    AND    NATATORIUMS.  23 

is  placed  upon  same,  thus  insuring  that  the  rim 
will  be  perfectly  molded. 

Another  style  of  mold  for  rim  is  shown  in  Fig. 
4.  This  may  be  used  upon  tubs  where  the  ends 
are  constructed  in  the  form  shown  in  illustration, 
also  as  a  rim  mold  upon  the  square  style  of  con- 
crete bath  tub. 

The  mold  is  easily  constructed  by  cutting  strips 
of  cove  or  scotia  moulding,  to  join^m  the  manner 
shown  in  the  illustration  at  Fig.  4.  The  two  con- 
cave sides  of  the  moulding  are  joined  together,  so 
to  make  the  semi-circular  channel  for  the  rim,  the 
largest  size  of  cove  molding  will  be  necessary 
so  to  give  the  rim  a  width  of  at  least  2%  inches. 
The  height  of  the  rim  may  be  changed  by  planing 
off  the  top  of  the  wood  molding,  if  that  is  con- 
sidered desirable. 

The  wood  mold  for  rim  must  be  well  coated  with 
shellac  and  also  given  a  coating  of  oil  before  the 
work  is  molded,  so  that  the  wood  will  not  absorb 
the  moisture  from  the  concrete,  and  also  to  pre- 
vent the  concrete  from  adhering  to  same  and  thus 
spoiling  the  cast. 

The  mold  for  rim  should  be  in  several  sections, 
so  to  be  the  more  easily  removed  from  the  molded 
work.  These  may  be  held  together  when  molding 
the  tub  by  strips  of  strap  iron  fastened  with 
screws,  as  explained  for  the  outside  sections  of 
bath  tub  mold;  or  the  sections  may  also  be  fas- 
tened together  with  hooks  and  eyelets  upon  the 


24  MOLDING   CONCRETE   BATH   TUBS, 


FIG.   5. — Tho   plnstor  system  of  molding  a   bath  tub. 


AQUAEIUMS    AND    NATATORIUMS.  25 

outside,  or  by  blocks  of  wood  nailed  to  the  mold- 
ing board  along  the  outside  of  rim  mold. 

THE  PLASTER  SYSTEM  OF  MOLDING 

The  plaster  system  of  molding  a  concrete  bath 
tub,  as  illustrated  in  Fig.  5,  is  practically  the  same 
as  that  employed  for  the  method  shown  in  Fig.  2, 
with  the  exception  that  the  outside  form  is  not 
used.  The  concrete  mortar  or  stucco  is  plastered 
upon  metal  lath,  which  are  placed  over  a  core 
form,  to  aid  in  holding  the  lath  into  position 
against  the  pressure  of  applying  the  plaster. 

The  wire  cloth  or  expanded  metal  lath  are  fitted 
together  to  conform  to  the  outline  of  the  bath  tub, 
then  placed  over  the  core  form  and  the  stucco 
applied;  when  the  concrete  is  sufficiently  hard- 
ened, the  work  is  turned  over  and  the  core  form 
removed ;  then  the  inside  of  tub  is  given  a  plaster 
coating  of  cement  mortar,  if  needed.  Usually  the 
mortar  may  be  pressed  through  the  wire  lath  and 
up  against  the  core,  so  to  make  the  inside  plaster- 
ing of  the  work  unnecessary. 

This  system  of  molding  makes  it  possible  to 
produce  a  bath  tub  that  is  far  less  in  weight,  with 
ample  strength  for  the  purpose  than  when  pro- 
duced in  molds.  By  having  a  number  of  core 
forms,  the  worker  can  perfect  as  many  tubs  each 
day  as  he  may  have  time  to  complete,  as  there  is 
not  the  necessity  of  waiting  for  the  concrete  to 
harden  before  the  outside  form  is  removed. 


26 


MOLDING   CONCRETE   BATH   TUBS, 


(3. — Molds  for  the  square  style  of  bath  tub. 


AQTJAKIUMS    AND    STATATORIUMS.  27 

MOLDING  THE  SQUARE  STYLE  OF  BATH  TUB 

The  simplest  style  of  molded  bath  tub  is  shown 
in  Fig.  6.  This  requires  a  simple  box  form  for  the 
outside  centering,  or  mold  to  the  tub,  which  is  or- 
namented by  panels. 

This  style  of  tub  is  usually  molded  in  the  posi- 
tion it  should  occupy,  as  its  weight  does  not  make 
it  possible  to  be  moved  very  easily.  To  mold  this 
upright,  the  core  must  be  suspended  in  the  proper 
position  by  strips  placed  across  the  top  of  the  out- 
side molds,  and  the  concrete  poured  or  tamped 
around  core.  By  placing  the  concrete  for  the  bot- 
tom of  tub  first,  before  setting  the  core  form  in 
the  center  of  mold,  the  perfect  molding  of  the  bot- 
tom is  assured. 

The  sides  of  tub  may  be  ornamented  by  mold- 
ing panels  of  concrete  of  a  contrasting  color  to 
that  used  in  the  body  of  the  tub,  and  then  insert- 
ing in  the  outside  molds  at  the  proper  point,  thus 
producing  an  excellent  appearance  to  the  com- 
pleted work.  The  panels  to  be  imbedded  into  the 
concrete  may  be  molded  with  a  smooth,  glossy 
surface,  so  to  reflect  light,  by  using  glass  slabs  in 
the  bottom  of  mold  for  panels,  thus  producing  a 
very  smooth  surface  to  the  molded  panel.  This 
method  is  fully  described  in  No.  5  of  this  series 
on  MOLDING  AND  CUBING  ORNAMENTAL 
CONCEETE. 

In  many  residences  where  there  is  but  little 


28  MOLDING   CONCRETE   BATH   TUBS, 

room  for  the  bath  tub,  and  without  any  possibility 
of  having  a  separate  room  for  the  purpose,  the 
style  of  tub  shown  in  Fig.  6  will  be  of  value,  as  it 
can  be  equipped  with  a  cover,  which  will  also 
serve  as  a  table  top  in  the  kitchen  or  any  room 
in  which  the  tub  may  be  placed.  This  can  be 
easily  removed  when  it  is  desired  to  use  the  tub. 
The  details  of  constructing  the  outside  forms 
for  this  style  of  bath  tub  is  clearly  shown  in  the 
illustration,  and  permit  of  many  changes  to  suit 
the  wishes  of  the  worker. 

MOLDING  THE  LEGS  FOR  BATH  TUBS 

The  easiest  method  of  molding  the  legs  for  a 
concrete  bath  tub  is  shown  in  Fig.  7.  This  re- 
quires that  the  outline  of  the  legs  be  cut  from  a 
board  of  the  right  width,  and  this  is  then  spaced 
the  correct  distance  apart  by  tacking  strips  of  tin 
or  sheet  metal  to  the  edges  of  the  wood  forms, 
except  at  the  point  where  the  legs  join  onto  the 
tub  and  also  at  the  top  of  form,  or  the  point  upon 
legs  that  rest  upon  the  floor,  which  is  left  open 
for  convenience  in  pouring  the  concrete. 

The  mold  for  the  legs  should  be  placed  upon 
the  bottom  of  bath  tub  as  soon  as  the  bottom  of 
same  is  finished,  so  that  the  concrete  will  be  firmly 
bonded  together.  In  event  this  is  not  done,  the 
point  where  the  legs  are  placed  should  have  the 
aggregate  exposed  by  scrubbing  with  a  stiff  brusli 


AQUARIUMS    AND    NATATORIUMS. 


29 


FIG.  7. — Molding  legs  to  bath  tubs. 


30  MOLDING  CONCRETE   BATH  TUBS, 

and  water,  so  that  the  concrete  placed  for  the  legs 
will  be  firmly  bonded. 

This  permits  the  legs  of  tub  to  be  placed  at  any 
point  the  worker  may  desire. 

The  method  of  cutting  the  wood  outline  of  the 
legs  is  shown  in  Fig.  8,  with  several  styles  that 
may  be  employed  for  this  purpose  with  excellent 
results. 

The  concrete  bath  tub,  when  molded  in  the  rein- 
forced type,  is  less  in  weight  than  a  tub  of  marble, 
and  about  the  weight  of  those  in  solid  porcelain. 
The  tub  should  be  carefully  water-proofed,  and 
may  be  finished  with  a  water-proof  enamel  upon 
both  outside  and  inside  surfaces,  if  desired. 

MOLDING  CONCRETE  LAVATORIES 

The  lavatory  shown  in  Fig.  9  is  easily  and  sim- 
ply molded  in  concrete.  The  bowl  is  molded  in  a 
square  box  form  that  has  a  moulding  along  tin1 
top  edge,  to  produce  the  ornamented  edge  to  same. 
The  mold  for  the  bowl  may  be  made  of  an  earthen- 
ware  bowl  or  a  small  chopping-bowl  of  the  right 
size,  or  it  may  also  be  formed  in  plaster  or  con- 
crete to  the  desired  shape.  Openings  are  molded 
in  the  lavatory  for  the  water  supply  pipes,  to  be 
placed,  by  inserting  iron  or  wood  plugs  of  the 
right  size  inside  the  mold  at  that  point.  These 
are  well  greased,  so  that  the  concrete  cannot  bond 
to  same. 

The  bowl  should  also  have  metal  strips  molded 


AQUARIUMS    AND    NATATOKIUMS.  31 


FIG.  8. — Several  styles  of  legs  for  bath  tubs. 


32  MOLDING   CONCRETE   BATH   TUBS, 

so  to  project  from  the  bottom  of  same.  These  are 
bent  at  right  angles,  and  enable  the  lavatory  to 
be  fastened  securely  to  the  wall.  The  bowl  is  also 
supported  in  front  by  legs  molded  of  concrete,  or 
by  employing  metal  legs  for  the  purpose. 

The  slab  at  back  of  lavatory  is  the  easiest 
molded  in  a  square  box  form,  that  is  lined  upon 
three  sides  with  wood  moulding,  so  to  produce 
an  ornamental  edge  to  the  slab.  If  the  face  of 
slab  is  molded  upon  a  sheet  of  glass,  using  a  mix- 
ture of  marble  flour,  white  sand  and  white  Port- 
land cement,  it  will  be  very  smooth  and  glossy 
and  reflect  light  like  polished  marble.  This  may 
have  openings  molded  in  same  for  placing  any 
water  supply  pipes,  if  so  desired.  The  slab  has 
a  small  i/i-inch  hole  molded  at  each  corner,  into 
which  screws  are  placed  for  fastening  the  slab 
against  the  wall. 

This  lavatory  may  also  be  molded  with  larger 
legs,  similar  to  those  used  for  the  laundry  tub 
shown  in  Fig.  10,  and  thus  it  may  be  placed  in  the 
center  of  floor,  instead  of  against  the  wall  line. 

An  excellent  style  of  lavatory  may  be  molded 
by  placing  the  core  form  in  the  center  of  molding 
board,  around  this  a  ring  or  circular  form  is 
placed,  constructed  from  sheet  metal;  this  circle 
should  be  at  least  6  to  8  inches  larger  than  the 
greatest  diameter  of  the  lavatory  bowl,  and  from 
2y2  to  3  inches  in  height.  The  concrete  for  bowl 
is  placed  inside  this  ring  and  over  the  core  form 


AQUARIUMS    AND    NATATORIUMS. 


33 


FIG.  9. — A  lavatory  that  is  easily  molded  in  concrete. 


34  MOLDING   CONCRETE   BATH  TUBS, 

for  molding  the  bowl,  to  a  depth  of  not  less  than 
2  inches;  where  this  is  above  the  ring  of  metal, 
for  outside  form,  the  concrete  can  be  molded  with 
the  trowel  to  form  the  shape  desired.  A  short  sec- 
tion of  gas  pipe  is  placed  in  the  center  of  bowl, 
at  the  top,  thus  molding  the  opening  for  waste 
pipe.  The  pedestal  to  support  the  lavatory  bowl 
is  molded  by  using  a  cylinder  of  sheet  metal,  the 
exact  size  desired  for  the  shaft,  with  a  larger  ring 
of  about  2  or  3  inches  in  height  to  mold  the  base 
of  pedestal.  The  shaft  should  be  from  5  to  6 
inches  in  diameter,  and  the  base  about  12  to  14 
inches  in  diameter,  and  2  or  3  inches  high  for  a 
lavatory  bowl  of  18  to  22  inches  in  diameter  and 
9  to  11  inches  in  height.  The  concrete  is  first 
placed  inside  the  mold  for  base  of  pedestal,  and 
then  the  metal  cylindrical  mold  for  stem  is  placed 
upon  same,  and  the  concrete  poured  for  stem  or 
shaft.  A  section  of  gas  pipe  must  be  placed  inside 
the  shaft  and  base  of  pedestal,  exactly  in  the  cen- 
ter, to  be  used  as  the  waste  pipe  to  lavatory.  The 
supply  pipes  may  also  be  molded  in  the  concrete, 
by  inserting  the  supply  pipes  inside  the  lavatory 
bowl  at  the  proper  point;  then  if  a  %-inch  supply 
pipe  is  to  be  used,  place  a  1%-inch  gas  pipe,  well 
greased,  inside  the  mold  for  pedestal  at  the  proper 
point  for  supply  pipe.  This  permits  the  plumber 
to  connect  the  supply  pipe  to  those  in  bowl.  Then 
place  this  inside  the  opening  molded  in  pedestal. 
and  finish  the  connection  at  the  bottom  of  pedes- 


AQUAEIUMS    AND    NATATOEIUMS.  35 

tal  after  the  bowl  is  placed  upon  top  of  pedestal. 
The  waste  pipe  may  project  above  the  pedestal 
about  %  of  an  inch  more  than  the  thickness  of 
lavatory  bowl  at  bottom,  thus  permitting  the 
plumber  to  place  a  nut  upon  same,  which  not  only 
makes  the  opening  for  waste  pipe,  but  also  holds 
the  lavatory  bowl  upon  the  pedestal.  This  nut 
must  be  so  placed  that  the  top  of  same  is  flush 
with  the  bottom  of  bowl,  allowing  for  mortar 
joint,  so  to  permit  the  bowl  to  be  absolutely 
cleaned  each  time  it  is  emptied. 

This  style  of  molding  may  be  employed  for 
many  different  types  of  lavatories,  as  well  as  the 
manner  of  connecting  same  to  the  waste  and  water 
supply  systems.  The  concrete  lavatory  is  a  most 
profitable  line  for  the  worker,  as  it  enters  into 
competition  with  other  materials  that  command  a 
high  price,  hence  the  profit  for  the  work  would 
be  large.  By  using  a  good  marble  mixture  for 
your  concrete,  the  work  would  be  of  a  quality  that 
would  enable  it  to  successfully  compete  with  any 
other  material. 

This  is  as  easily  applied  to  many  styles  of 
bowls  for  closets ;  thus  the  type  known  as  a  plain 
hopper  or  bowl  is  as  easily  molded  as  the  bowl  for 
a  lavatory.  The  syphon  type  of  bowl  may  also 
be  perfected  in  concrete,  using  a  slightly  different 
form  than  is  usually  employed ;  in  this  the  trap  or 
syphon  is  molded  as  a  separate  unit  and  upon  this 
the  bowl  is  placed. 


36  MOLDING   CONCRETE   BATH  TUBS, 

A  strong  competitor  to  the  porcelain  kitchen 
sink  may  also  be  molded  in  nearly  the  same  man- 
ner as  employed  for  the  lavatory  bowl  and  apron, 
illustrated  in  Fig.  9.  The  outside  form  is  built 
in  the  same  manner  as  for  a  lavatory,  with  the 
inside  form  or  core  in  a  square  box  shape,  to 
mold  the  inside  surface  of  the  sink.  The  molds 
should  be  lined  with  sheet  metal  to  give  a  smooth 
molding  surface,  and  also  to  protect  the  wood 
against  the  moisture  in  the  concrete.  The  slab 
placed  against  the  wall  is  molded  in  the  same  man- 
ner as  employed  for  the  lavatory  slab,  illustrat«l 
in  Fig.  9.  This  must  have  openings  molded  in 
same  to  place  the  bibbs  and  water  supply  pipo 
for  sink.  The  bottom  of  sink  should  have  the 
strainer  or  waste  pipe  opening  molded  in  same,  or 
the  strainer  may  be  placed  at  the  time  the  con- 
crete is  poured  and  is  then  ready  for  connecting 
to  waste  pipe. 

Lavatories,  closet  bowls  or  hoppers,  as  well  as 
kitchen  sinks,  should  be  reinforced  with  wire  lath 
or  expanded  metal  lath,  thus  permitting  the  work 
to  be  amply  strong,  but  without  excessive  weight. 

MOLDING  CONCRETE  LAUNDRY  TUBS 

The  style  of  laundry  tub  illustrated  in  Fig.  10, 
is  easily  molded  in  concrete  for  either  a  two  or 
three  part  tub,  as  may  be  desired.  This  tub,  when 
carefully  molded,  is  fully  the  equal  of  a  composi- 
tion laundry  tub,  and  for  the  practical  use  to 


AQUAKIUMS    AND    NATATOEIUMS. 


FIG.   10. — Laundry  tub  or  tray  molded  in  concrete. 


MOLDING   CONCRETE   BATH   TUBS, 

which  it  is  to  be  applied,  it  would  be  a  strong 
rival  of  the  porcelain  tub,  as  the  price  would  aid 
in  making  it  popular. 

The  entire  length  of  the  tub  is  60  inches  over 
all ;  the  walls  are  made  2  inches  in  thickness,  and 
reinforced  with  wire  lath  or  expanded  metal  lath. 
Each  compartment  is  27x24  inches  and  16  inches 
deep,  making  the  total  height  of  the  tub  from  the 
floor,  3  feet  2  inches,  with  the  legs  20  inches  in 
height,  and  the  tub  above  same  18  inches  high 
upon  the  outside.  The  legs  are  molded  4  inches 
thick,  and  in  the  manner  illustrated,  or  any  other 
form  the  worker  may  desire. 

The  slab  at  the  back  is  12x60  inches  and  iy2 
inches  thick.  This  is  best  when  molded  sepa- 
rate from  the  tub  and  then  attached  to  the  wall 
with  screws,  above  the  top  of  the  compartments  of 
tub.  Openings  should  be  molded  in  the  slab  for 
placing  the  bibbs  and  pipes  for  water  supply,  also 
openings  in  the  bottom  of  each  compartment  for 
placing  the  waste  pipe  to  tub.  These  may  be  ar- 
ranged by  inserting  a  short  piece  of  gas  pipe,  pre- 
viously well  greased,  into  the  green  concrete  at 
the  point  the  opening  is  desired. 

This  tub,  in  either  the  two  or  three  compart- 
ment styles,  is  molded  in  the  manner  shown  in 
Fig.  11.  The  cores  are  made  of  wood,  covered 
with  sheet  metal,  in  size  equal  to  the  inside  dimen- 
sions of  each  compartment  of  the  tub.  The  core 
is  made  convex  on  the  top,  so  to  mold  the  bottom 


AQUARIUMS    AND    NATATOBIUMS. 


39 


FIG.   11. — Molding  concrete  laundry  tub. 


40  MOLDING   CONCRETE   BATH   TUBS, 

of  the  tub  in  a  concave  form,  which  makes  it  far 
more  satisfactory,  enabling  the  tub  to  be  easily 
emptied  of  all  waste  water.  The  convex  part  of 
core  is  easily  made  by  cutting  two  strips  of  wood 
in  that  form  and  then  covering  with  heavy  sheet 
metal,  to  form  the  molding  surface. 

The  cores  are  inverted  upon  the  molding  board 
at  the  proper  distance  apart,  where  they  are  held 
by  blocks  nailed  to  the  molding  board,  to  prevent 
the  cores  from  slipping  out  of  position  when  the 
concrete  is  tamped  or  poured  into  the  mold.  The 
back  and  front  sides  of  outside  mold  are  easily 
made  of  straight  boards  as  forms,  with  wood 
mouldings  along  the  edges  to  give  a  circular  edge 
to  the  tub,  if  that  is  desired. 

The  two  ends  of  the  tub  are  cut  from  lumber  in 
an  exact  outline  of  the  form  desired;  these  pro- 
ject 20  inches  above  the  form  for  main  body  of 
tub,  and  an  extra  form  for  legs  is  spaced  4  inches 
from  the  end  form,  so  as  to  mold  the  legs  of  tub 
at  each  end  of  same,  20x24  inches,  and  4  inches 
thick.  A  circle  or  any  other  shape  may  be  cut  in 
the  center  of  the  molds  for  legs,  and  a  sheet  of 
metal  bent  to  fit  into  same,  thus  molding  any 
opening  in  the  legs  that  the  worker  may  desire. 
This  opening  is  of  advantage  when  placing  the 
waste  pipe,  and  also  makes  the  complete  tub 
lighter  in  weight,  with  the  legs  amply  strong  for 
the  purpose. 

The  reinforcement  is  easily  placed,  as  the  tub 


AQUAEIUMS    AND    NATATORIUMS.  41 

is  molded  bottom  side  upward,  and  thus  every 
portion  of  same  is  within  sight  of  the  operator 
when  placing  the  concrete. 

The  wood  parts  of  mold  should  be  well  pro- 
tected against  moisture,  by  coating  with  a  good 
oil  compound,  such  as  equal  parts  of  petroleum 
and  linseed  oil ;  giving  the  wood  two  or  three  coats 
before  using  the  mold  and  then  a  light  coating 
each  time  before  the  mold  is  to  be  used.  This  not 
only  prevents  the  wood  portions  of  mold  from 
warping  and  checking,  but  also  prevents  the  con- 
crete from  adhering  to  the  wood,  caused  by  un- 
protected wood  absorbing  the  moisture  from  the 
concrete  and  carrying  with  it  particles  of  cement, 
which  penetrate  the  fibres  of  the  wood  and  thus 
bond  the  outside  concrete  to  the  wood  molding 
surface.  This  causes  the  surface  of  the  cast  to 
scale  or  break  off  pieces  when  the  molds  are  re- 
moved. The  oil  coating  prevents  this  trouble  and 
secures  a  good  cast  from  wood  molds,  that  have 
been  treated  each  time  before  using. 

MOLDING  A  COMPLETE  AQUARIUM 

The  style  of  aquarium  shown  in  Fig.  12  is  as 
easily  and  simply  molded  as  any  square  design  in 
concrete.  This  is  best  when  molded  with  glass  in- 
serted into  the  sides  of  same,  and  if  desired,  also 
in  both  ends  of  the  aquarium.  The  top  is  orna- 
mented by  lining  the  edge  of  mold  with  stock  wood 
mouldings  to  perfect  the  outline  desired. 


42 


MOLDING   CONCRETE   BATH   TUBS, 


Flo.   12. — Small  concrete  aquarium   with  glass  sides. 


AQUAKIUMS    AND    NATATOBIUMS.  43 

This  aquarium  is  designed  to  be  placed  upon  a 
pedestal,  hence  is  not  constructed  upon  a  large 
scale,  the  size  varying  to  suit  the  wishes  of  the 
worker. 

The  details  for  this  style  of  aquarium  are 
clearly  shown  in  Fig.  13,  also  the  manner  of  in- 
serting the  glass  sides  in  same.  The  forms  are 
constructed  of  wood,  in  nearly  the  same  manner 
as  if  a  panel  was  to  be  molded  in  the  concrete 
wall  of  cast.  The  edges  of  the  glass  are  then 
dipped  in  a  cement  composed  of  one  part  tallow 
melted  with  two  parts  of  rosin,  the  dipped  portion 
of  the  glass  should  be  equal  to  the  depth  it  is  to 
be  imbedded  in  the  concrete  along  each  edge.  The 
concrete  for  the  bottom  of  aquarium  is  placed, 
and  then  the  core  is  inserted  inside  the  outside 
forms,  and  to  rest  upon  the  concrete  placed  for 
bottom  of  cast. 

The  sheets  of  glass  are  then  slipped  between  the 
two  boards  that  mold  the  opening  in  sides,  with 
the  edges  of  the  glass  projecting  upon  each  side 
of  the  panel  boards,  and  also  the  bottom  edge  of 
glass  pressed  into  the  concrete  placed  for  bottom 
of  aquarium.  Thus  the  glass  is  firmly  imbedded 
in  the  cement  at  all  points.  The  mixture  of  rosin 
and  tallow  makes  an  elastic  putty,  or  cement,  that 
will  permit  the  concrete  to  expand  without  break- 
ing the  water-tight  joint.  The  putty  must  be  ap- 
plied hot,  and  as  this  is  also  applied  to  the  point 
where  glass  is  imbedded  in  the  concrete,  the  sides 


44 


MOLDING   CONCRETE   BATH   TUBS, 


13 — Manner  of  placing  the  glass  in  a  concrete  acquarium. 


AQUARIUMS    AND    NATATORIUMS.  45 

are  sealed  against  the  water  escaping,  in  the  same 
manner  as  putty  perfects  a  water-tight  joint  in 
the  ordinary  window  sash. 

The  walls  of  aquarium  may  be  reinforced  with 
wire  cloth  of  i/^-inch  mesh,  or  expanded  metal 
lath,  if  the  size  of  wall  will  permit  its  use.  This 
permits  the  thickness  of  wall  to  be  from  1*4 
to  2  inches  in  thickness,  as  may  be  demanded  by 
the  size  of  the  work  to  be  molded.  As  shown  in 
Fig.  13,  the  core  is  built  in  sections.  These  are 
held  together  with  screws  when  molding  the  aqua- 
rium; thus  permitting  the  core  to  be  taken  apart 
when  removing  from  the  complete  cast,  and  les- 
sening the  danger  of  injuring  the  work,  as  would 
be  the  case  if  the  core  was  not  divided  in  this 
manner. 

DESIGN  FOR  A  LARGE  CONCRETE  AQUARIUM 

At  Fig.  14  is  shown  a  simple  and  most  excellent 
design  for  a  large  concrete  aquarium.  As  will  be 
noted  from  the  illustration,  there  is  ample  space 
underneath  the  tank  to  place  the  water  supply 
pipes.  The  bottom  of  tank  is  placed  at  the  correct 
height  for  its  contents  to  be  viewed  easily,  with 
the  bottom  of  tank  about  8  inches  in  width,  and 
from  that  sloping  upward  in  a  gentle  declivity  to 
the  top.  This  compels  the  fish  or  other  aquatic 
inhabitants  of  the  tank  to  stay  close  to  the  glass 
side,  where  they  may  be  the  more  easily  viewed. 

This  style  of  aquarium  is  designed  to  stand 


46  MOLDING   CONCRETE   BATH   TUBS, 


FIG.    14. — Sectional    view   of   a   large   concrete   aquarium. 


AQUAKIUMS    AND    NATATORIUMS.  47 

against  the  wall,  thus  making  it  practical  for  any 
public  structure.  The  ledge  upon  one  side  is  eas- 
ily molded  by  using  wood  mouldings  inside  the 
mold  at  that  point.  The  glass  side  may  be  in- 
serted in  the  same  manner  as  for  the  small  aqua- 
rium, which  was  illustrated  in  Fig.  13. 

This  aquarium  may  be  built  in  sections,  with 
partition  walls  at  equal  distances  apart,  so  to  ac- 
commodate many  different  species  of  fish,  etc. 
The  vertical  walls  for  the  front  and  partitions  of 
the  tank  may  be  2y2  inches  in  thickness  for  a 
small  size  of  aquarium,  and  from  this  varying  to 
3  inches  for  larger  sizes,  when  reinforced  with 
metal  lath  imbedded  into  the  wall.  The  sloping 
wall  at  back  of  tank  should  be  from  3  to  4  inches 
in  thickness,  and  amply  reinforced  with  expanded 
metal  lath.  The  floor  of  tank  is  molded  from  4% 
to  6  inches  in  thickness,  depending  upon  the  size 
of  the  aquarium.  The  legs  or  walls  supporting 
the  tank  are  best  when  molded  4y2  to  5  inches  in 
thickness;  the  sloping  wall  at  back  should  have 
openings  not  only  to  admit  the  supply  pipes,  but 
also  to  permit  any  one  to  enter  same  so  to  make 
repairs  to  these  pipes  when  it  is  needed. 

CONCRETE  AQUARIUMS  FOR  OUTSIDE  USE 

A  method  of  constructing  concrete  aquariums 
for  outside  use  is  shown  in  Fig.  15.  These  may 
be  either  square  or  in  any  other  form  the  worker 
may  desire,  and  by  constructing  in  a  series  with 


48 


MOLDING   CONCRETE   BATH   TUBS, 


FlO.    15. — Method   of   arranging    concrete   aquariums. 


AQUARIUMS    AND    NATATOBIUMS.  49 

each  one  slightly  higher  than  those  below,  the 
water  can  run  from  the  upper  tank  to  the  lowest 
in  the  series.  This  is  of  advantage  for  trout  and 
all  fish  demanding  a  constant  supply  of  fresh 
water,  the  series  of  tanks  securing  the  advantage 
of  a  brook  with  different  species  of  fish  in  each 
tank,  and  all  filled  from  the  one  supply  pipe. 

The  manner  of  molding  these  tanks  is  clearly 
shown  in  the  illustration,  so  that  the  worker 
should  have-  no  difficulty  in  perfecting  same.  By 
arranging  the  tanks  or  aquariums  upon  a  terrace, 
with  the  top  edge  of  each  one  even  with  the  ground 
line  of  lawn,  the  effect  is  very  pleasing. 

MOLDING  CONCRETE  NATATORIUMS 

The  usual  method  of  molding  a  concrete  nata- 
torium  or  swimming  pool,  with  the  method  of 
water-proofing  same,  is  shown  in  Fig.  16.  The 
forms  are  constructed  for  the  outside  wall  and 
braced  in  position,  the  core  form  is  then  sus- 
pended inside  of  the  outside  centering,  by  strips 
across  the  top.  The  concrete  for  bottom  of  the 
tank  is  first  placed  for  about  one-half  of  its  thick- 
ness, and  the  core  forms  set  so  to  mold  about  one- 
half  of  the  outside  wall,  or  that  portion  next  to 
the  outside  centering. 

The  core  form  is  built  in  sections  so  to  be  the 
more  easily  taken  apart  and  removed  from  the 
work,  as  well  as  to  be  adjustable  to  the  two  sec- 
tions of  wall  built  by  this  method. 


50 


MOLDING   CONCRETE   BATH   TUBS, 


k-i  .r  •  •/.—  "  •""  •          -.    -v   v1  "•  ^  r .' "  .- 
;>.•••••..•   ..•-••-•         •....•     :.•..-....•  -,,  •  •  • 


FIG.  16. — Molding  and  water-proofing  a  concrete  natatorium. 


AQUARIUMS    AND    NATATOBIUMS.  51 

When  the  concrete  has  hardened  enough  to  per- 
mit, the  core  form  is  removed,  and  the  inside  of 
the  tank  given  a  thick  coat  of  asphalt,  or  even 
hot  tar,  tarred  felt,  or  some  perfect  water-proof- 
ing material  that  will  also  act  as  a  binder  or  ad- 
hesive between  the  two  layers  of  concrete.  The 
balance  or  second  layer  of  the  floor  is  then  laid 
upon  this  asphalt  coating  and  the  core  erected  to  . 
complete  the  wall  to  the  desired  thickness,  the 
concrete  being  placed  for  same  as  soon  as  the 
asphalt  coating  is  in  place. 

This  method  places  an  absolute  water-proof 
layer  of  material  between  the  two  sections  of  wall 
and  floor,  as  shown  by  the  dotted  lines  in  Fig.  16. 
By  having  it  nearly  in  the  center  of  wall  each 
layer  of  concrete  is  thick  enough  to  stand  the 
loading  without  cracking,  even  if  the  bond  between 
layers  is  not  perfect. 

The  concrete  pool  or  tank  should  be  sloping 
with  the  greatest  width  at  the  top,  so  that  in 
event  of  the  water  in  same  freezing  at  any  time, 
the  pressure  would  be  far  less  than  if  the  sides 
were  vertical. 

The  outside  wall  should  have  a  footing  of  suffi- 
cient width  to  support  the  wall.  This  must  rest 
upon  solid  ground  or  a  foundation  wall  that  is 
amply  strong  enough  for  the  load,  so  that  there 
is  no  possible  danger  of  the  wall  settling  and  thus 
causing  the  concrete  to  crack  and  injure  the  use- 
fulness of  the  work.  Where  there  is  any  danger 


52  MOLDING   CONCRETE   BATH  TUBS, 

from  this  cause,  or  in  large  pools  of  this  kind,  the 
work  should  have  ample  reinforcement  by  tying 
expanded  metal  or  wire  lath  to  steel  rods  or  bars 
spaced  at  the  proper  distance  apart  to  take  all 
the  strain. 

The  concrete  for  the  foundation  may  be  mixed 
1:3:6,  using  sharp  sand,  running  from  coarse  to 
fine,  and  gravel  not  to  exceed  2  inches  in  diameter, 
where  the  foundation  walls  are  placed  in  a  trench 
and  below  ground.  This  is  covered  with  a  6-inch 
course  of  1:2:4  mixture,  well  tamped,  at  the 
ground  line.  The  body  of  the  large  pool  may  be 
built  of  well  graded  aggregates  in  the  proportions 
of  1:2:4,  using  gravel  or  broken  stone  as  the 
large  aggregate.  This  is  plastered  upon  the  in- 
side with  a  coating  of  one  part  Portland  cement 
to  two  parts  of  clean,  sharp  sand.  The  concrete 
must  be  mixed  wet  and  well  tamped  or  forced  into 
place,  so  to  reduce  the  amount  of  voids,  allowing 
the  forms  to  remain  about  two  to  three  days,  so 
to  permit  the  concrete  to  harden  before  removing 
to  apply  the  plaster  coat. 

Openings  for  inlet  and  outlet  are  made  by  in- 
serting short  sections  of  iron  pipe  in  the  concrete, 
or  by  using  a  tapering  wood  plug  or  form  for 
opening.  These  should  be  well  greased,  so  to 
prevent  the  concrete  from  adhering  to  same. 


AQUARIUMS    AND    NATATORIUMS.  53 

WATER-PROOF  CONCRETE 

Concrete  that  is  made  properly,  so  to  secure  the 
maximum  density,  is  practically  impervious  to 
water  with  a  low  pressure.  In  this  regard  the 
proper  proportioning  of  the  materials,  grading 
the  aggregates  so  to  leave  the  least  percentage  of 
voids,  care  and  thoroughness  in  mixing,  and  the 
use  of  water  in  a  quanity  ample  to  thoroughly  wet 
the  mixture,  are  of  the  greatest  importance  in 
securing  a  dense  and  water-proof  concrete.  It  is 
also  of  importance  that  the  concrete  should  be  a 
rich  mix,  where  the  work  will  permit,  and  if  this 
is  not  possible,  as  upon  large  tanks,  the  inside 
surface  should  be  plastered  with  a  rich  mixture. 

A  rich  mixture  of  concrete  where  subjected  to 
a  low  water  pressure  is  usually  impermeable,  and 
this  increases  with  the  age  of  the  work. 

Where  the  joints  occur  in  the  work,  special  care 
should  be  given  to  the  water-proofing,  so  that 
water-tightness  may  be  assured. 

The  water  pressure  against  the  surface  of  the 
concrete,  must  be  considered  in  estimating  the 
necessary  water-proofing  treatment.  This  is  usu- 
ally from  15  pounds  to  156  pounds  per  square  foot 
of  wall  surface,  and  with  a  lifting  pressure  under 
a  floor  of  31  pounds  to  312  pounds  per  square  foot, 
for  a  hydrostatic  head  of  6  inches  to  5  feet;  for 
a  head  up  to  10  feet,  the  pressure  against  the 
wall  per  square  foot  will  be  up  to  312  pounds,  and 


54  MOLDING   CONCRETE   BATH  TUBS, 

under  a  floor  this  will  be  doubled,  or  624  pounds 
to  the  square  foot.  With  a  head  of  15  feet,  the 
wall  pressure  will  be  468  pounds  against  each 
square  foot  of  the  wall  surface;  20  feet  gives  a 
wall  pressure  of  625  pounds ;  25  feet  a  pressure 
of  781  pounds  to  the  square  foot  of  wall  surface. 
With  a  hydrostatic  head  of  30  feet,  the  pressure 
against  the  wall  will  be  937  pounds ;  above  30  feet 
in  hydrostatic  head  the  average  pressure  is  easily 
estimated  by  multiplying  the  pressure  at  20  feet, 
or  625  pounds,  by  the  number  of  times  20  feet  is 
contained  in  the  estimated  hydrostatic  head.  The 
lifting  or  pressure  under  a  floor  surface  is  usually 
estimated  at  double  the  water  pressure  against  <i 
vertical  wall. 

VARIOUS   METHODS   OF   WATER-PROOFING 

Among  the  oldest  methods  of  surface  treatment 
processes  for  water-proofing  concrete,  the  Syl- 
vester process  has  been  the  most  universally  em- 
ployed. This  required  the  application  of  alter- 
nate coatings  of  soap  and  alum  solutions,  applied 
hot.  The  castile  soap  is  dissolved  in  hot  water, 
using  three-quarters  of  one  pound  to  each  gallon 
of  water.  This  is  spread  over  the  surface  with  a 
brush.  About  24  hours  later,  a  solution  of  8 
ounces  of  powdered  alum  to  each  four  gallons  of 
water  is  applied  over  the  soap  coating.  These 
alternate  coatings  are  repeated  at  intervals  of 
24  hours  apart,  usually  about  four  coats  of  both 


AQUAKIUMS    AND    NATATORIUMS.  55 

the  soap  and  alum  solutions  is  demanded  to  se- 
cure the  desired  result. 

Another  method  of  employing  this  process  is  to 
add  one  pound  of  the  powdered  alum  to  each  sack 
of  cement  used,  and  mixing  with  the  water  used 
for  the  concrete  one  per  cent,  of  ordinary  soft 
soap. 

To  tanks,  boiled  linseed  oil,  applied  in  successive 
coatings,  has  also  been  successful,  as  well  as  the 
application  of  tar  and  asphalt.  A  wash  or  coat- 
ing of  one  part  green  vitriol  in  three  to  four  parts 
of  water  has  also  secured  success  in  water-proof- 
ing many  small  articles,  where  the  surface  was  of 
no  great  area. 

The  use  of  hydrated  lime  is  of  value  when  10% 
to  25%  has  been  added  to  the  concrete  mixture. 
This,  by  its  exceptional  fineness,  fills  the  voids  in 
the  work  that  would  otherwise  be  open  for  the 
passage  of  moisture. 

A  wash  of  Portland  cement  and  hydrated  lime, 
mixed  one  part  lime,  by  weight,  to  two  parts  of 
Portland  cement,  and  applied  to  the  wall  surface 
with  a  brush,  has  been  very  effective  in  water- 
proofing the  concrete  where  the  water  pressure 
was  not  too  great.  This  wash  or  coating  will  be 
far  more  effective  and  spread  easier,  filling  the 
pores  and  defects  in  the  work  and  making  a 
smoother  surface,  if  2  ounces  of  powdered  alum 
has  been  added  to  each  gallon  of  the  brush  coat. 

A  number  of  the  water-proofing  and  stone  finish 


56  MOLDING   CONCRETE   BATH   TUBS, 

compounds  now  in  use  are  made  up  of  hydrated 
lime  and  Portland  cement  as  the  base  of  the  com- 
pound. The  success  of  these  finishes  proves  the 
value  of  the  lime  and  cement  brush  coat  as  a 
water-proofing  coating,  when  thoroughly  and  care- 
fully applied. 

The  use  of  paraffin  as  a  water-proofing  ma- 
terial has  met  with  good  success,  and  for  small 
articles  the  process  would  be  of  use  and  value. 
There  are  various  methods  of  applying  the 
paraffin  to  the  concrete,  either  by  keeping  it  in  a 
melted  state,  which  may  be  done  by  subjecting 
the  vessel  holding  same  to  a  gentle  heat  while 
the  coating  is  placed  over  the  surface  with  a 
brush,  or  by  cutting  the  paraffin  into  very  small 
pieces  and  placing  in  gasoline  or  any  quickly 
evaporated  or  volatilized  fluid  and  then  applying 
this  to  the  surface;  as  soon  as  the  gasoline  has 
evaporated,  so  it  is  safe  to  do  so,  a  torch  can  be 
used  for  heating  the  concrete  surface  and  thus 
causing  the  paraffin  to  penetrate  the  pores  of  the 
concrete,  where  it  immediately  hardens  and  com- 
pletely fills  the  openings,  thus  preventing  the  pas- 
sage of  water. 

Another  method  is  to  heat  the  concrete  sur- 
face with  the  torch,  before  applying  the  paraffin, 
and  then  going  over  the  work  again  with  the  torch 
to  complete  the  process.  This  has  an  advantage 
in  the  fact  that  the  paraffin  will  remain  in  a 
liquid  or  melted  state  longer  than  where  the  wall 


AQUAKIUMS    AND    NATATOKIUMS.  57 

has  been  subjected  to  the  heat  but  once,  thus  en- 
abling it  to  penetrate  to  a  greater  depth  below 
the  concrete  surface  and  increase  the  value  of  the 
protective  and  water-proof  coating. 

The  use  of  sodium  silicate  (water  glass)  in  the 
proportion  of  one  part  to  three  parts  of  water 
and  this  applied  to  the  concrete  surface,  has  given 
excellent  results.  This  is  a  very  cheap  method 
of  water-proofing,  as  the  usual  cost  of  the  water 
glass  is  from  one  to  two  cents  a  pound,  depending 
upon  the  quantity  purchased.  This  readily  mixes 
with  water,  thinning  the  sodium  silicate  so  to  the 
more  readily  enter  the  pores  of  the  concrete. 

Several  applications  should  be  made,  so  to  fill 
the  pores  of  the  work.  This  will  result  in  a  por- 
tion of  the  material  remaining  upon  the  surface, 
and  may  be  flushed  off  with  water,  or,  better  yet, 
sprayed  with  chloride  of  calcium  (chloride  of 
lime),  which  forms  a  chemical  reaction  when  in 
contact  with  the  water  glass,  hardening  the  sur- 
face of  the  concrete  and  making  a  surface  imper- 
vious to  moisture.  While  the  application  of  the 
chloride  of  lime  will  lighten  the  surface  of  the 
concrete,  yet  it  supplies  the  necessary  lime  to 
harden  the  sodium  silicate  and  form  an  insoluble 
coating  upon  the  concrete  surface.  Where  the 
chloride  of  lime  solution  is  not  applied,  the  water 
glass  that  is  flushed  to  the  surface  of  the  concrete 
is  washed  off  with  water,  leaving  only  the  sodium 
silicate  solution  that  has  penetrated  the  pores, 


58  MOLDING   CONCRETE    BATH   TUBS, 

and  from  contact  with  the  lime  and  alkalies  in  the 
concrete,  has  hardened  into  an  insoluble  coating 
that  will  render  the  concrete  impervious  to  water. 

Small  articles  may  be  immersed  in  the  sodium 
silicate  bath,  and  by  remaining  in  same  from  12 
to  24  hours,  will  absorb  more  of  the  solution  than 
if  it  is  applied  as  a  surface  treatment,  producing 
more  satisfactory  results. 

In  using  any  water-proofing  material,  it  must 
be  remembered  that  the  porosity  of  the  concrete 
must  determine  the  success  or  failure  of  the 
water-proofing  material.  Thus,  a  lean  mixture  of 
concrete  with  poorly  graded  aggregates  and  indif- 
ferent care  in  the  mixing  and  placing,  will  pro- 
duce a  greater  percentage  of  voids  in  the  work. 
This  demands  more  material,  labor  and  care  to 
water-proof  effectively  than  if  the  concrete  is  of 
the  maximum  density.  It  will  thus  be  seen  that 
the  water-proofing  problem  must  be  judged  in  ac- 
cordance with  the  condition  of  the  wall,  and  that  a 
treatment  that  was  effective  on  a  perfect  wall 
would  be  a  failure  when  applied  in  the  same  man- 
ner to  a  far  more  porous  surface.  The  one  safe 
and  effective  rule  for  a  water-proof  surface  is  to 
produce  the  maximum  density  to  the  concrete. 
The  use  of  a  rich  and  wet  mixture  with  clean  and 
properly  graded  aggregates  will  go  far  towards 
the  purpose  desired. 


AQUARIUMS    AND    NATATORIUMS.  59 

PATENT  COMPOUNDS  FOR  WATER-PROOFING 

A  brief  mention  of  the  various  special  com- 
pounds on  the  market  may  interest  the  reader. 
While  it  would  not  be  within  my  province  to  ad- 
vise the  use  of  any  one  compound  instead  of  an- 
other, yet  the  brief  description  given  may  enable 
the  reader  to  decide  upon  the  one  most  suitable 
to  his  needs. 

Among  the  products  intended  to  be  incorpo- 
rated with  the  concrete  we  have  a  number  in  pow- 
der form,  thus  ANHYDEA  is  a  white  powder  re- 
sembling talcum  powder,  and  is  added  to  the  neat 
cement  in  the  proportion  of  about  two  per  cent., 
by  weight,  to  the  weight  of  the  cement  used,  or 
2  pounds  to  the  sack. 

There  are  a  number  of  brands  of  hydrated  lime 
placed  upon  the  market  under  different  trade 
names,  and  which  demand  that  from  10  to  25  per 
cent.,  by  weight,  be  incorporated  with  the  cement 
used. 

In  the  dry  powder  form  we  have  HYDEA- 
TITE,  which  is  mixed  with  the  dry  cement  in  the 
proportion  of  about  2  pounds  to  the  sack  of  ce- 
ment, and  then  the  damp  sand  added  to  same. 
The  IDEAL  WATEE-PEOOF  FILLEE  is  also 
mixed  with  the  dry  cement  in  proportions  of  1  to 
2  pounds  to  each  sack  of  cement.  MEDUSA 
WATEE-PEOOF  COMPOUND  is  another  pow- 
der form  of  water-proofing  compound,  and  is  usu- 


60  MOLDING   CONCRETE    BATH   TUBS, 

ally  mixed  with  the  dry  cement  in  a  proportion  of 
1  to  2  pounds  to  each  sack  of  cement  used.  TOX- 
EMENT  is  said  to  be  effective  when  mixed  2 
pounds  to  the  sack  of  cement,  while  dry. 

AQUABAR  is  a  paste-like  solution,  which  is 
placed  in  the  water  employed  for  mixing  the  con- 
crete, using  one  part  of  the  compound  to  twenty- 
four  parts  water. 

The  compound  sold  under  the  trade  name  of 
ANTI-HYDRO  is  mixed  in  the  proportions  of  one 
part  of  the  solution  to  ten  parts  of  water,  used  in 
mixing  the  cement.  This  is  largely  used  in  plas- 
ter coatings,  applying  a  coating  of  neat  cement; 
a  scratch  coat,  %  of  an  inch  thick,  mixed  1 :2,  and 
a  finish  coat  %  of  an  inch  thick,  mixed  1 :1,  using 
the  compound  in  the  water  employed  for  mixing 
the  mortar. 

Another  dry  powder  compound  is  sold  as 
"TRUS-CON"  WATER-PROOFING  FILLER, 
and  is  mixed  with  the  cement  while  in  a  dry  state, 
in  the  proportion  of  2  pounds  to  the  sack.  This 
is  often  employed  in  plaster  coatings  as  well. 

Among  the  compounds  employed  for  the  sur- 
face treatment  of  concrete,  ANTIHYDRINE  is 
described  as  a  high  grade  of  asphalt  in  combina- 
tion with  other  chemicals  that  forms  a  glossy  and 
impervious  coating  over  the  concrete  surface, 
when  applied  with  a  brush,  each  gallon  covering 
about  100  square  feet. 

CEMELINE  is  a  liquid  water-proofing  mate- 


AQUARIUMS    AND    NATATORIUMS.  61 

rial  that  is  supplied  in  various  colors  and  is  em- 
ployed with  CEALTITE  as  a  filler  or  putty-like 
composition  for  sealing  the  joints  and  cracks  in 
the  wall. 

The  DEHYDEATINE  DAMP-BE  SIS  TING 
COMPOUNDS  are  heavy  black  liquids  that  are 
applied  cold,  with  a  brush,  with  a  covering  capac- 
ity of  50  to  80  square  feet  to  the  gallon.  DIA- 
MOND WATEE-PEOOFING  is  a  mineral  solu- 
tion that  is  claimed  for  it  to  be  insoluble  in  water 
and  without  containing  any  grease,  oil  or  paraf- 
fin. It  is  applied  with  a  brush,  like  ordinary 
paint. 

IEONITE  is  another  mineral  compound  in  the 
form  of  a  fine  powder,  which  is  mixed  with  water 
to  the  consistency  of  a  brush  coat.  When  first 
applied,  the  color  is  black,  but  in  time  this  changes 
to  a  brown  shade.  This  is  claimed  to  effectively 
resist  water  pressure.  LIQUID  KONKEEIT  is 
also  spread  like  paint,  as  well  as  TE-PE-CO.,  the 
latter  having  a  covering  capacity  of  85  to  125 
square  feet  to  the  gallon. 

While  there  are  a  number  of  other  compounds 
for  which  perfect  results  are  claimed  when  ap- 
plied to  the  concrete  surface,  yet  in  the  main,  any 
water-proofing  mixture  must  largely  depend  upon 
the  density  of  the  concrete  for  its  success,  as 
where  the  pores  or  voids  are  larger  than  will  per- 
mit the  filler  or  compound  to  perfectly  close  same, 
effective  water-proofing  cannot  be  expected,  thus 


62  MOLDING   CONCRETE   BATH   TUBS, 

bringing  the  worker  back  to  the  fact  that  unless 
the  concrete  has  been  properly  made,  or  at  least 
protected  by  a  rich  and  dense  plaster  coating,  im- 
permeability cannot  be  secured  with  certain 
success. 


INDEX 

PAGE 

Advantages  of  a  wet  mix  of  concrete 13, 14 

Advantages  of  the  square  style  of  bath  tub 28 

Aquarium,  how  molded 41_49 

Aquarium  for  outside  use 47_49 

Assembling  a  concrete  lavatory 34, 35 

Asphalt  as  a  water-proofing  material 51 

Bath  tub  molds,  construction  of 16_18 

Bonding  sections  of  bath  tubs 28.30 

Brush  coat  of  neat  cement  and  lime,  use  of 55 

Cement    for   aquariums 43 

Chloride  of  calcium,  how  used 57 

Closet  bowls  molded  in  concrete 35 

Coating  core  mold  to  prevent  sticking 16 

Concrete  for  natatoriums 52 

Core  for  bath  tubs,  construction  of 14_16 

Cores   for  laundry   tubs 38_40 

Density,  how  secured  without  pressure 13 

Design  for  a  large  concrete  aquarium 45, 46 

Details  of  molding  laundry  tub 38 

Forms  for  molding  bath  tub  legs 30,  31 

Hydrated  lime,  used  for  water-proofing 55 

Inserting  glass  in  concrete  aquariums 43 

Kitchen  sinks,  molded  in  concrete 36 

Laundry  tubs  of  concrete 36_41 

Lavatories,  how  molded 30_36 

Legs  to  bath  tubs,  how  molded ' .          "  28.30 

Legs  to  laundry  tubs,  how  molded 40 

Lime  In  concrete,  how  used .','.'.'.  13.55.59 

Linseed  oil  as  a  water-proofing  compound  55 

63 


64  MOLDING   CONCRETE   BATH   TUBS, 

Marble  concrete  for  lavatory  and  bath  tub 32 

Metal  strips,  to  fasten  lavatory  to  wall 32 

Mix  of  concrete  for  bath  tub  and  aquarium 13, 14 

Molding  a  concrete  bath  tub 18 

Molding  a  concrete  lavatory 30-30 

Molding  concrete  kitchen  sinks 36 

Molding  concrete  laundry  tubs  or  trays 38_40 

Natatoriuins,   how  molded 49-52 

Oil  compound  for  coating  wood  molds 41 

Ormunental  sides  to  bath  tubs,  how  molded 19.21 

Panels  for  ornamental  bath  tub 27 

Paraffin,  use  in  water-proofing  concrete 56 

Patent  compounds  for  water-proofing 59.62 

Pedestal   lavatory,  how  molded 32.35 

Plaster  mold  for  rim  of  bath  tub 21 

Plaster  system  of  molding  bath  tubs 25 

Reinforcement,   when   necessary 14 

Reinforcement  of  bath  tubs 19 

Rim  of  bath  tub,  how  molded 21.23 

Sand,  grade  used  for  securing  water-proof  concrete....        14 

Sodium  silicate,   how   used 57 

Square  style  of  bath  tub,  how  molded 27,  28 

Supply  pipes,  how  placed  in  lavatory 30.34 

Swimming  pools,   how  molded 49.52 

Sylvester   process   of   water-proofing 54, 55 

Test  of  sand  for  loam  or  clay 14 

Thickness  of  walls,  of  bath  tubs 19 

Vitriol  wash  for  water-proofing 55 

Water  pressure  against  walls  and  floor 53 

Warping  of  wood  molds,  how  prevented 41 

Water-proofing  a  concrete  natatorium 51 

Water-proofing  concrete 53.61! 

\Vood  mold  for  rim  of  bath  tub 23 

Wood  molds,  how  protected  from  moisture 41 


CATALOGUE  OF 
STANDARD 
PRACTICAL  AND 
SCIENTIFIC 
BOOKS 


PUBLISHED  AND  FOR  SALE  BY 

The  Norman  W,  Henley  Publishing  Go, 

132  Nassau  St.,  New  York,  U.  S.  A. 


INDEX  OF  SUBJECTS 

Brazing  and  Soldering 3 

Cams n 

Charts 3 

Chemistry 4 

Civil  Engineering 

Coke 4 

Compressed  Air 4 

Concrete 5 

Dictionaries 5 

Dies— Metal  Work 6 

Drawing— Sketching  Paper 6 

Electricity 7 

Enameling 9 

Factory  Management,  etc 9 

Fuel 10 

Gas  Engines  and  Gas 10 

Gearing  and  Cams n 

Hydraulics n 

Ice  and  Refrigeration n 

Inventions— Patents 12 

Lathe  Practice 12 

Liquid  Air 12 

Locomotive  Engineering 12 

Machine   Shop  Practice 14 

Manual  Training 17 

Marine  Engineering 17 

Metal  Work-Dies 6 

Mining 17 

Miscellaneous 18 

Patents  and  Inventions 12 

Pattern  Making 18 

Perfumery 18 

Plumbing 19 

Receipt  Book. ...  24 

Refrigeration  and  Ice u 

Rubber 19 

Saws 20 

Screw  Cutting 20 

Sheet  Metal  Work 20 

Soldering 3 

Steam  Engineering 20 

Steam  Heating  and  Ventilation 22 

Steam  Pipes 22 

Steel 22 

Watch  Making 23 

Wireless  Telephones 23 


Any  of  these  books  will  be  sent  prepaid  to  any   part  of 
f  the  world,  on  receipt  of  price. 

REMIT  by  Draft.  Postal  Money  Order,  Express  Money  Order 
or  by  Registered  Mail. 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 

AN  INITIAL  FINE  OF  25  CENTS 

WILL  BE  ASSESSED  FOR  FAILURE  TO  RETURN 
THIS  BOOK  ON  THE  DATE  DUE.  THE  PENALTY 
WILL  INCREASE  TO  SO  CENTS  ON  THE  FOURTH 
DAY  AND  TO  $1.OO  ON  THE  SEVENTH  DAY 
OVERDUE. 


Z- 


1935 


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30JuP5fiBB 


mi  2 

30Mr'59CB 


Lp 


1959 


Due  end  of  SPRING  Quart* 

-CiihiftH-   fr*   rorail    aftQf  -* 


API 


RETURNED  TO 


IUN  -  6  1971 


'MOEF1TT 


-100m-8,'34 


A 


221002 


, 


